The mobile communication system has been developed for the user to communicate on the move. With the rapid advance of technologies, the mobile communication system has evolved to the level capable of providing high speed data communication service as well as voice telephony service. Meanwhile, with the advent of high processing devices, auxiliary memory devices, and display devices, the user terminal manufacturing technology has developed to the extent that the smartphones capable of providing the user with high speed high quality data communication services on the move are popularized.
The development of high speed data communication service and widespread use of high performance smartphones spur the advent of novel user application services. Representative examples thereof include high quality multimedia video provision service (e.g. YouTube), Social Networking Service making it possible for users to share information and activity (e.g. Facebook), and search service allowing users to find information anytime anywhere (e.g. google).
The next generation application service providers are developing Context Aware Service technologies competitively to provide the more enhanced user experience. The context aware service is the technology of predicting the user's ultimate goal in the current situation based on the service usage history of the user to improve the user convenience. Accordingly, in order to provide the user with the context aware service, the service provider has to collect and retain the information previous user activity and service usage history information such as visited webpages, used keywords, viewed videos, communicated persons, frequently visited areas. As the amount of collected user information (i.e. context) increases, the context aware service can be provided more precisely.
However, the context aware service is likely to invade personal privacy in the process that the server collects information. There is therefore a need of developing the method capable of providing enriched context aware service without invading personal privacy.